The present invention relates to a double-faced vacuum fluorescent display device and a method for driving same, wherein the device has a front plate, a back plate and an anode electrode containing a fluorescent layer formed thereon.
A conventional double-faced vacuum fluorescent display device is normally provided with a front plate, a back plate, front anode electrodes formed on the front plate and back anode electrodes formed on the back plate, each anode electrode containing a fluorescent layer coated thereon, wherein a grid is installed corresponding to each anode electrode and a filament is tightly hanged between two grids facing each other.
FIG. 15A shows a plan view of a conventional double-faced vacuum fluorescent display device 700. FIG. 15B illustrates a cross sectional view of the conventional double-faced fluorescent display device 700 taken along X-Xxe2x80x2of FIG. 15A.
In FIGS. 15A and 15B, there are illustrated a front plate 71 of the fluorescent device 700, a front anode electrode 72 formed on the front plate 71 and a grid 74 corresponding thereto installed facing the front anode electrode 72, wherein a fluorescent layer 73 is coated on the front anode electrode 72. Further, there are illustrated a back plate 75 of the fluorescent device 700, a back anode electrode 76 formed on the back plate 75 and a grid 78 corresponding thereto installed facing the back anode electrode 76, wherein a fluorescent layer 77 is coated on the back anode electrode 76. A filament 79 is tightly hanged between the two grids 74 and 78 by two supporting members 80 and 80xe2x80x2 disposed on the front plate 71. The grids 74 and 78 control the electron emission from the filament 79 toward the front anode electrode 72 and the back anode electrode 76 facing each other, respectively.
Since, however, in the conventional double-faced vacuum fluorescent display device 700, the grids 74 and 78 should be installed between the front anode electrode 72 and the back anode electrode 76, the fluorescent display device 700 is expensive, structurally complex and it is especially difficult to manufacture a light and slim type one. Further, the manufacturing process of the fluorescent display device 700 may be accompanied by certain other defects. For example, the alignment of the grids with the anode electrodes is difficult; and there occurs considerable power consumption due to the use of the grids.
It is, therefore, an object of the present invention to provide a simple and slim double-faced vacuum fluorescent display device whose power consumption and fabrication cost are low.
In accordance with a preferred embodiment of the present invention, there is provided a double-faced vacuum fluorescent display device including a front plate, a back plate and a filament installed between the front plate and the back plate facing each other,
characterized in that the front plate has one or more front anode electrodes and the back plate has one or more back anode electrodes, each anode electrode containing a fluorescent layer coated thereon; the front anode electrodes function as control electrodes to control the electron emission from the filament toward the back anode electrodes; and the back anode electrodes function as control electrodes to control the electron emission from the filament toward the front anode electrodes.
In accordance with another preferred embodiment of the present invention, there is provided a double-faced vacuum fluorescent display device including a front plate, a back plate and a filament installed between the front plate and the back plate facing each other,
characterized in that the front plate has one or more front anode electrodes and the back plate has one or more back anode electrodes, each anode electrode containing a fluorescent layer coated thereon; and when the front anode electrodes are selected to be turned on to emit light, the back anode electrodes function as control electrodes to control the electron emission from the filament toward the front anode electrodes; and when the back anode electrodes are selected to be turned on to emit light, the front anode electrodes function as control electrodes to control the electron emission from the filament toward the back anode electrodes.